JAIN SLEE

Dima Ionut Daniel

Contents• What is JAIN SLEE?• Basic Concepts

– Resource Adaptor– Activity/ActivityContext– Events– Services– SBB– Deployable Unit– Profiles– Usage Parameters

• SBB Lifecycle• Facilities• Management• Resource Adaptor

• Transactions• SLEE Vendors• Mobicents SLEE

– Diameter Base RA• Conclusions• Bibliography

What is JAIN SLEE?

• SLEE stands for Service Logic Execution Environment.• JAIN stands for Java APIs for Intelligent Networks• JAIN SLEE is Java based "Write once – Run anywhere".• JAIN SLEE is standardized in Java Community Process:

– JAIN SLEE 1.0 --> JSR 22– JAIN SLEE 1.1 --> JSR 240

• JAIN is an enabling set of Java APIs to develop and deploy service driven network applications and services.

~2005

What is JAIN SLEE? (cont.)

• JSLEE - low latency and high throughput application server for event processing

Basic Concepts

• Every component type is a Deployable Unit (DU)• Concurrency control is implemented by the environment, not the application.• JSLEE is event driven and knows producer consumer relationships.

Basic Concepts (cont.)

• JSR 22 was finished in 03 Mar 2004.– defines Service Resource API interface

• JSR 240 was finished in 14 Jul 2008.– defines Service Resource Adaptor interface

Basic Concepts

Resource Adaptor

Resource Adaptor

• External resources are represented in SLEE by Resource Adaptors(RA)• RA adapts an external resource for use by services in the SLEE• System level component• Incoming flow (external resource -> SLEE): modeled as events• Outgoing flow (SLEE -> external resource): modeled as method invocations on objects provided by the RA• RA submits events via a 'SleeEndpoint'; SLEE routes the events to 0 or more SBBs.• A "plugin" adapts a network protocol to JSLEE event based communication.

Basic Concepts

Activity/ActivityContext

Activity/ActivityContext

• An Activity is a Java interface that represents a conversation with another system.• Commonly Activities model Sessions, Dialogs or Protocol Request / Response pairs• Activities are in the resource domain• Events are delivered on Activities.• Events are routed to SBB that are interested in them• Activity ==> Event ==> SBB• Each Activity has an ActivityContext.• JSLEE does not define the API for an Activity; the Resource Adaptor provides its own APIs.

Activity /ActivityContext (cont.)

• An Activity object resides within the resource domain.

• An Activity Context resides in the SLEE domain to represent an underlying Activity object in the resource domain.

Activity /ActivityContext (cont.)

• An ActivityContext can be in 3 states:– Active– Ending– Invalid

• The lifecycle state of an ActivityContext is transactional.

Basic Concepts

Events

Events

• Events represents some occurence of significants.• Events originate from a number of places: external places, SLEE, other services• SLEE services are triggered by events and process events• Events are Deployable Units, having: name, vendor, version.• The act of passing an event from its source to its destination is termed "Event Routing" in JSLEE.

Basic Concepts

Services

Services

• Service is a deployment artifact defined by a Service 'deployment descriptor' that is deployed in the SLEE.• Service is a collection of one or more SBBs. One of the SBBs is the 'Root SBB'.• A service instance consists of one or more SBB instances of the type of SBB in the Service.• SBB instances in the same Service may process events concurrently.

Basic Concepts

SBB

SBB

• SBB stands for Service Building Blocks.• An SBB component defines:

– event types received and generated by the SBB component– Per-instance state is stored in CMP(Container Managed Persistent) fields that the SLEE manages– Event handler methods. – Local interface methods: defines the operations of the SBB component that may be invoked sync.– Child relations: an SBB component may be composed of 0 or more child SBB components.– Shareable state: SBB defines the state that it may share with the other components as a set of Activity Context properties.

SBB (cont.)

• An SBB’s component identity uniquely identifies an SBB component: sbb-name + sbb-vendor + sbb-version• The SbbID class defines the interface of a Java object that encapsulates an SBB’s component identity. • The SBB local interface must extend the javax.slee.SbbLocalObject interface.• The SBB abstract class is mandatory and implements the javax.slee.Sbb interface.• SBB methods:

– Event handler methods– Local interface methods– Life cycle callback methods– An sbbExceptionThrown callback method– An sbbRolledBack callback method– Initial event selector methods

SBB (cont.)

• An SBB object is an instance of the SLEE generated class that extends the SBB abstract class• The SLEE creates and manages a pool of SBB objects.• It can receive and fire events, receive synchronous method invocations, and access and update the persistent

state of the SBB entity.• SBB interfaces and classes naming convention:

– SBB abstract class <name>Sbb– SBB Activity Context Interface interface <name>SbbActivityContextInterface– SBB local interface <name>SbbLocalObject

SBB (cont.)

• The HelloSleeWorldSbb implements the javax.slee.Sbb inteface.

SBB (cont.)

• The SBB definition is needed for SLEE vendor application server.• It contains the abstract SBB class and the events that the SBB is interested in.

SBB (cont.)

• The deployable unit contains the service xml file that contains the metadata.

Basic Concepts

Deployable Unit

Deployable unit

• A deployable unit is a Jar file that can be installed in the SLEE.• A deployable unit may contain Services, SBB jar files, event jar files, Profile Specification jar files, resource

adaptor type jar files, resource adaptor jar files, and library jar files. • Each of these jar files contain the Java class files and the deployment descriptors of one or more of these

components.

Basic Concepts

Profiles

Profiles

• Provisioned data required by the SBB to perform its function. E.g. configuration data or per subscriber data. • For each Profile Specification, the Profile Specification Developer provides the following parts:

– A profile CMP interface– An optional Profile Local Interface

• The Profile Specification Developer may provide an optional Profile Local interface.• This interface declares the methods that should be visible to SLEE Components such as SBBs, Resource

Adaptors, or other Profile Specifications.

Basic Concepts

Usage Parameters

Usage Parameters

• A usage parameter is a parameter that can be updated by an object in the SLEE to provide usage infomation.• It is accessible by the Administrator through the management interface of the SLEE.• Each usage parameter is addressed by a hierarchically scoped name:

– Notification source name component: identifies the SLEE entity such as an SBB, Profile Table or RA entity.– Usage parameter set name component: identifies a usage parameter set accssible by the notification source.– Usage parameter name component: is the lowest-level scoped name and identifies a usage parameter by the notification

source name component.

SBB Lifecycle

Does Not Exist state The SBB object does not exist. It may not have been created or it may have been deleted.

Pooled stateThe SBB object exists but is not assigned to any particular SBB entity.

Ready stateThe SBB object in the Ready state is assigned to an SBB entity. It is ready to receive events

Facilities

• Facilities are standard functional components provided by the SLEE

Facilities (cont.)

• The SLEE specification defines the following standard Facilities:– Timer Facility

• for initiating periodic actions– Alarm Facility

• Used by SBBs, RA, Profiles to request the SLEE to raise or clear alarms.– Trace Facility

• Generates trace messages intended for consumtion by external management clients.– Activity Context Naming Facility

• Provides a global flat namespace for naming Activity Contexts– Profile Facility

• Allows SBBs to obtain the ProfileTable object or ProfileTableActivity object for a specified ProfileTable.– Event Lookup Facility

• Used by RA to obtain information about the event types installed in the SLEE.– Service Lookup Facility

• Used by RA to obtain information about the types of events a Service installed in the SLEE may receive.

Management

• The SLEE specification provides management capabilities for deployable units, Services, Resource Adaptors, Profile Tables, Profiles, the Alarm Facility, and the Trace Facility.

• A management client manages the SLEE by interacting with a set of SLEE specification defined MBean objects, as defined by the Java Management Extension (JMX) specification.

• The SLEE Mbean interfaces are Mbeans interfaces defined by the SLEE specification; thise interfaces are defined in the javax.slee.management package.

• Example Mbean interfaces: SleeManagementMBean, ServiceManagementMBean, ServiceUsageMBnea, AlarmMBean, TraceMBean, ResourceManagementMBean, ProfileTableUsageMBean,etc.

Management (cont.)

• Requirements of any management client that accesses the SLEE Mbean objects:– Client may only reference a SLEE MBean object by its Object Name.– Client can only invoke a SLEE MBean object through a local or remote MBean Server.

• There are two approaches to implementing a custom SLEE management client.– implement the client as a MLet MBean.– implement a SLEE management client using the JMX Remote API.

• The requirements of a management client MLet MBean are:– it can be implemented as any type of MBean supported by the JMX 1.2.1 specification.– should implement the javax.management.MBeanRegistration interface.

Management (cont.)

• There are lots of MBean objects that provide the external management interface of the SLEE.

Resource Adaptor

• Resources are entities that represent and interact with other systems outside the SLEE, such as network devices, protocol stacks,databases, directories, etc.

• Resource adaptors adapt particular resources to the requirements of the SLEE.• Resource adaptor receives messages from external sources and submits them as events to the SLEE.• The SLEE Resource Adaptor architecture consists of APIs which are implemented by the SLEE:

– Resource adaptor type• Defines the API and a contract that SBB use to interact with the Resource

– Resource adaptor• Implementation of one or more resource adaptor types.

– Resource adaptor entity• Represents the mapping within the SLEE of a particular resource as adapted by a RA. • Multiple resource adaptor entities may be created from a single RA.

– Resource adaptor object• RA objects are Java objects that the SLEE uses to interact with RA entities.

– SLEE Endpoint• Integrace used by a RA object to start Activities, fire Events on Activities and end Activities.

Resource Adaptor (cont.)

Meta model of the Resource Adaptor architecture

Resource Adaptor (cont.)

• A resource adaptor entity can be in one the following 3 operational states:– Inactive

• The RA entity is ready to be activated.– Active

• The RA adaptor entity has been activated.– Stopping

• The RA entity is being deactivated.

Resource Adaptor (cont.)

• Resource adaptor class requirements:– RA class must be defined in a named package.– class must implement javax.slee.resource.ResourceAdaptor interface– class must be defined as public and cannot be abstract or final.– class must have a public no-argument constructor

• Resource adaptor object lifecycle:– Unconfigured state– Inactive state– Active state– Stopping state

Transactions

• All SLEEs must implement the transactional semantics defined in this specification.• All transactions are isolated from each other at the serializable isolation level.• The SLEE starts a transaction prior to a SLEE originated invocation sequence.• A resource adaptor object may also start and commit or rollback transactions for its own use.

Transactions

• A transaction may be in one of the following states:– Active:

• Transaction is typically created and initialized prior to the SLEE originated invocation sequence.– Committing

• On successful completion of SLEE originated invocation sequence the transaction transitions from Active to Committing state.

– Committed• Transition enters in this state when a heuristic has likely been applied.

– Marked for Rollback• Extension of the transaction life cycle provided by the SLEE.

– Rolling Back• A transaction in this state is in the process of rolling back.

– Rolled Back• Tra.nsaction has been aborted

SLEE Vendors

• There are 2 SLEE vendors:1. Mobicents2. Rhino from OpenCloud

• Mobicents is an Open Source VoIP Platform written in Java to help create, deploy, manage services and applications integrating voice, video and data across a range of IP and legacy communications networks.

• OpenCloud Rhino Telecom Application Server is the world-leading converged carrier-grade Telecom Application Server (TAS).

• Rhino Telecoms Application Server complies with both Java telecom application server standards – JAIN SLEE (JSLEE) and SIP Servlet.

Mobicents SLEE

• Mobicents can be installed on Tomcat or Jboss.• The Mobicents managements can be found at http://localhost:8080/slee-management-console.

Mobicents SLEE (cont.)

• The JAIN SLEE specification includes an API for interaction with JAIN SLEE container.• External applications can connect via interface javax.slee.connection.SleeConnectionFactory and fire events.• JAIN SLEE provides two different implementations of the API, one for access in the same JVM, another for remote

access.

Mobicents SLEE (cont.)

• Mobicents JSLEE Twiddle is command line tool, based on JBoss JMX.• Mobicents JSLEE Twiddle acts on base of command and operation.• Command supports various operations.• Operation is aware of specific resource that needs to be called and how it should be accessed to perform certain

task.

Mobicents SLEE (cont.)

• twiddle.sh [options] <command> [command_arguments] • slee command interacts with javax.slee.management:name=SleeManagement

Mobicents

Diameter Base RA

Diameter Base RA

• Diameter Base Resource Adaptor Type is defined by Mobicents team as part of effort to standardize RA Types.• Diameter Base Type defines the following Activities:

– AuthClientSessionActivity: client side of Base Authentication session. Abort-Session-Request (ASR) and Re-Auth-Request (RAR) messages are received in this Activity

– AuthServerSessionActivity: represents server side of Base Authentication session. – AccountingClientSessionActivity: represents client side of Base Accounting session. Accounting-Request (ACR) messages can

be created and sent in this Activity.– AccountingServerSessionActivity: represents server side of Base Accounting session. Accounting-Request(ACR) messages are

received in this Activity.– DiameterActvity: represents a generic Diameter session

Diameter Base RA (cont.)

• Events received on Authorization Client Activity : SessionTerminationRequest, AbortSessionAnswer, ReAuthAnswer, ErrorAnswer, AbortSessionRequest, SessionTerminationAnswer, ReAuthRequest, ErrorAnswer.

• Events received on Accounting Server Activity: AccountingRequest• Events received on Accounting Client Activity: AccountingAnswer, ErrorAnswer.• Events received on Generic Diameter Activity: ExtensionDiameterMessage, ErrorAnswer,

CapabilitiesExchangeRequest, CapabilitiesExchangeAnswer, DeviceWatchdogRequest, DeviceWatchdogAnswer, DisconnectPeerRequest, DisconnectPeerAnswer.

• The Mobicents Diameter Base Resource Adaptor SBB Interface provides SBBs with access to the Diameter objects required for creating and sending messages using the interface DiameterProvider.

Conclusions

• JAIN SLEE is used in the telephony.• For telephony, data and wireless communications networks the API brings:

– Service portability– Network independe– Open development

• SLEE can be used to interface with other application servers and services.

Bibliography

• JAIN SLEE (JSLEE) 1.1 Specification, Final Release• Mobicents User Guide